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<html>
<head>
<meta charset="utf-8">
<title>20187821018张慧琴</title>
</head>

<body>
<form action="" method="post">请输入一个年份<input name="y" type="text"><input name="sub" type="submit" value="判断是否是闰年"></form>
<?php
$year=$_POST["y"];
$Cyear=$year/4;
if(isset($_POST["sub"]))
{
	$year=$_POST["y"];
	if($year%400==0||($year%4==0&&$year%100!=0))
	{echo $year."是闰年 <br/>";
     echo "$year/4=$Cyear";}
	else 
	{echo $year."不是闰年 <br/>";
     echo "$year/4=$Cyear";}
	}
?>
</body>
</html>